I hear that for a business sense, however the pool of treasures items is not really that small. So when you're getting four of the same armor it's just ludicrous

I don't disagree at all. However when the developers care more about squeezing every penny from their fan base rather than making the players happy, I see why they drop duplicates so frequently. I think you can get up to 7 sterling treasures a week though, so I don't see why anyone would want to spend their money on them.